Knives which fold into handles are common and known as pocket knives. Pocket knives suffer in varying degrees from three limitations; the length of the blade that can be held in the handle, the appearance of the handle when the blade is extended, and the stability of the blade when it is extended.
U.S. Pat. No. 1,270,727 teaches a pocket knife which effectively stores the blade in the handle; however, it limits the blade length to the length of the handle. The handle is bifurcated, forming two halves, one of which pivots from a closed position where the halves abut and are in a side-by-side relationship forming a handle to a position where the halves meet at a right angle. A spring is provided to urge the handle elements into the side-by-side relationship.
The difficulty relating to the limited length of the blade which can be stored has in part been overcome by U.S. Pat. No. 770,118 where the handle elements are designed to overlap in the closed position. The structure is limited to construction from sheet type material and thus, lacks the strength and integrity which can be obtained from a solid handle.
The problem of the integrity of the handle has in part been overcome by U.S. Pat. No. 728,416 and U.S. Pat. No. 924,070, both of which disclose an internally mounted tail which pivots about a position within the handle thus, decreasing the length of the blade, when compared with the blade of the '118 patent, which can be accommodated. The handle, when closed with the blade extended, does not have the smooth contours possessed by conventional hunting knives. Knives such as those taught by the '416 and '070 patents also have a discontinuity in the handle when the handle is open to store the blade. The '070 patent illustrates the discontinuity in the width that occurs when the blade is stored in the handle.
U.S. Pat. No. 947,980 illustrates a knife where the tail is mounted in the butt end increasing the length of the blade that can be accommodated by the knife handle. However, this knife still results in a discontinuity in the contour of the handle when it is open to store the blade. Furthermore, the design of the '980 patent requires the narrowing of the guard region of the knife which further distinguishes the appearance from conventional hunting knives.
Thus, there is a need for a knife where the handle will accommodate a long blade and yet provide a conventional appearing camping or hunting knife when in the open position.